With Specified Local Oscillator Structure Or Coupling Patents (Class 455/318)
  • Patent number: 7650119
    Abstract: A wireless communication device is disclosed wherein the voltage swing of a local oscillator (LO) signal is controlled to prevent overstressing semiconductor devices in a mixer to which the LO signal is supplied. A quadrature divider supplies the LO signal to the mixer. Digital calibration methodology controls the current that the quadrature divider draws from a power supply to set the voltage swing of the LO signal that the quadrature divider generates.
    Type: Grant
    Filed: January 27, 2006
    Date of Patent: January 19, 2010
    Assignee: Silicon Laboratories Inc.
    Inventors: Aslam A. Rafi, Donald A. Kerth
  • Patent number: 7639762
    Abstract: A receiver architecture for receiving an FSK signal having a predetermined number of modulation levels includes a selectivity filter (206) for selectively passing a wanted channel and rejecting unwanted channels. The selectivity filter has a filter bandwidth of about one-half the bandwidth of a pre-modulation filter in a transmitter sending the FSK signal. A discriminator (208) is coupled to the selectivity filter for demodulating the signal. A symbol recovery processor (210) is coupled to the discriminator for recovering the symbols through a maximum likelihood sequence estimation (MLSE) technique utilizing N states for each symbol time, wherein N equals the predetermined number of modulation levels, and wherein templates used in the MLSE for symbol transitions are optimized with a bandwidth substantially less than the bandwidth of the pre-modulation filter.
    Type: Grant
    Filed: April 22, 2008
    Date of Patent: December 29, 2009
    Assignee: Freescale Semiconductor, Inc.
    Inventor: Chen Weizhong
  • Patent number: 7630700
    Abstract: A frequency-mixing device performing voltage multiplying and low-pass filtering operations in addition to frequency mixing is provided. The three operations may be carried out with the same components by designing the frequency mixer appropriately. The frequency mixer comprises a first capacitance connected in series to the input of the frequency-mixing device, a first switch connected in parallel to the first capacitance, a second switch connected in series to the first capacitance, and a second capacitance connected in parallel to the second switching means. The switches are controlled by a local oscillator signal to close and open alternately according to a change in the voltage level of the first oscillator signal.
    Type: Grant
    Filed: July 27, 2006
    Date of Patent: December 8, 2009
    Assignee: Nokia Corporation
    Inventor: Risto Väisänen
  • Publication number: 20090286500
    Abstract: A method and frequency converter for a radio rapid frequency signal scanning and including a local oscillator signal synthesis source (112) producing a local oscillator signal (502) with local oscillator bursts (210). The local oscillator bursts (210) contain pulse width modulated RF frequency pulses (602). Each local oscillator burst having, for a pre-determined duration, RF frequency pulses within an effective amplitude above a pre-determined threshold (260). Each local oscillator burst (210) having also has effective amplitude pulse shaping envelope (504) that reduces at least one frequency domain component magnitude (310) of the local oscillator signal (300). A radio frequency mixer (110) receives an RF signal input (104) and the local oscillator signal to produce an output signal (160) at a frequency related to a combination of a frequency of the RF signal input and a frequency of the local oscillator signal.
    Type: Application
    Filed: May 15, 2008
    Publication date: November 19, 2009
    Applicant: Motorola, Inc.
    Inventor: ROBERT E. STENGEL
  • Publication number: 20090280767
    Abstract: A passive, differential RF mixer reduces second order intermodulation interference while maintaining I/Q isolation via common mode feedback wherein the I and Q error signals in the feedback path are time multiplexing using a four-phase LO signal. An RF signal is received at a differential input having a center tap. The RF signal is mixed with an in-phase differential signal of the four-phase local oscillator signal in a differential mixer (I mixer). The RF signal is also mixed with a quadrature-phase differential signal Q components of the four-phase local oscillator signal in a differential mixer (Q mixer). The common mode levels of the I and Q differential mixer outputs are compared to a reference DC voltage to generate I and Q error signals. The I and Q error signals are time-multiplexed, and fed back to the RF input center tap.
    Type: Application
    Filed: May 9, 2008
    Publication date: November 12, 2009
    Inventor: Fredrik Tillman
  • Patent number: 7610033
    Abstract: A radio frequency tuner is provided having inputs for receiving signals in common or overlapping frequency ranges from distribution networks. Each input is connected to a respective first converter, for example performing upconversion to a first intermediate frequency above the RF frequency ranges of the incoming signals. The first frequency changers are arranged to be active one at a time. The outputs of the first frequency changers are supplied to a second frequency changer which performs downconversion on the output signal of the active first converter to convert a selected channel from one of the distribution networks to a second intermediate frequency. Sufficient RF isolation may therefore be provided without requiring mechanical switching components such as RF relays.
    Type: Grant
    Filed: January 17, 2006
    Date of Patent: October 27, 2009
    Assignee: Intel Corporation
    Inventors: Nicholas Paul Cowley, Peter Coe
  • Patent number: 7603095
    Abstract: The present invention provides a way of hysteretic switching for efficiently reducing the heavy switching between two adjacent coarse intervals. The present invention disposes a number of fine intervals to cover a range which is larger than the length of one coarse interval. Each coarse interval comprises some extra fine intervals which are exceeded the boundary of the coarse intervals in one side. The heavy switching will be postponed until the extra fine intervals are used up. In the meantime, the fine calibration unit records the number of extra fine interval which be used. An extra-boundary value will be recorded in the fine calibration unit for determining an initial fine interval in another coarse interval if the heavy switching occurs. It should be noted that the extra-boundary value could be a positive or minus value corresponding to which a forward coarse interval or a backward coarse interval the reference signal drifts into.
    Type: Grant
    Filed: February 17, 2006
    Date of Patent: October 13, 2009
    Assignee: Silicon Integrated Systems Corp.
    Inventors: Chia-hao Yang, Chia-jung Liu
  • Publication number: 20090253396
    Abstract: A wireless communication apparatus includes a local oscillator that generates a plurality of LO (Local Oschillation) signals corresponding to frequencies of a plurality of input RF (Radio Frequency) signals, an accumulator that accumulates the plurality of LO signals generated by the local oscillator to generate an accumulated signal, a mixer that mixes the plurality of RF signals and the accumulated signal generated by the accumulator and to generate a plurality of base band signals, and a first signal processing unit that executes a signal process with respect to the plurality of base band signals generated by the mixer.
    Type: Application
    Filed: March 20, 2009
    Publication date: October 8, 2009
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Jun DEGUCHI, Shouhei Kousai, Daisuke Miyashita
  • Patent number: 7577416
    Abstract: A single balanced mixer has a high degree of isolation between an IF signal and an RF signal and a high conversion efficiency. The single balanced mixer includes means for producing two local signals of same amplitude and opposite phase, a pair of mixing elements each receiving a corresponding one of the two local signals, a pair of strip lines for transmitting the input RF signal to the mixing elements. One end of each of the strip lines is connected to one another at a point where the RF signal is supplied and other end of each of the strip lines is connected to the corresponding mixing element. A length of each of the strip lines is one fourth of a wave length of the IF signal.
    Type: Grant
    Filed: January 8, 2001
    Date of Patent: August 18, 2009
    Assignee: Advantest Corp.
    Inventor: Masayuki Kimishima
  • Publication number: 20090170465
    Abstract: The present invention discloses a mixer comprising with an input stage (100) for receiving and amplifying input signals (VINP, VINN) and an output stage (300) for outputting output signals (Voutp, Voutn). A switching stage (200) is coupled between the input stage (100) and the output stage (300), the switching stage (200) mixing the amplified input signals with a local oscillator signal (vlop, vlon) to produce the output signals (Voutp, Voutn) at the output stage (300). An RC circuit (cop, rop; con, ron) is connected to the output stage (300) and adapted to move the pole of the output signals.
    Type: Application
    Filed: December 31, 2007
    Publication date: July 2, 2009
    Applicant: MIPSABG Chipidea, Lda.
    Inventor: Ricardo dos Santos REIS
  • Patent number: 7555280
    Abstract: An apparatus for frequency direct conversion reception in a mobile communication terminal and method thereof are disclosed, by which a DC offset can be removed.
    Type: Grant
    Filed: December 6, 2005
    Date of Patent: June 30, 2009
    Assignee: LG Electronics Inc.
    Inventor: Sang Won Kim
  • Patent number: 7555281
    Abstract: A level comparator supplied with oscillation signal of local oscillator for comparing the signal level of oscillation signal with a certain predetermined threshold value, and a driving section interposed between the output of level comparator and a control section are provided. When the level comparator recognized that the signal level exceeded the threshold value, it puts the driving section into operation for bringing the control section into action.
    Type: Grant
    Filed: September 13, 2006
    Date of Patent: June 30, 2009
    Assignee: Panasonic Corporation
    Inventors: Takashi Umeda, Atsuhito Terao, Motoyoshi Kitagawa
  • Patent number: 7536164
    Abstract: A technique includes selectively coupling impedances to an oscillator to establish a first frequency of operation of the oscillator. The technique includes repeating the selective coupling in a feedback loop to cause the first frequency to be near a second frequency.
    Type: Grant
    Filed: April 22, 2005
    Date of Patent: May 19, 2009
    Assignee: Silicon Laboratories Inc.
    Inventors: James P. Maligeorgos, Dylan A. Hester, Augusto M. Marques, G. Tyson Tuttle
  • Patent number: 7536165
    Abstract: A direct conversion receiver includes a detector that provides a measure of bias offset that is caused by component mismatches in the direct conversion mixer, and a corrective network that reduces the bias offset based on this measure. The direct conversion mixer demodulates a radio-frequency (RF) input signal via mixing with a local-oscillator (LO) signal to provide a differential baseband output signal. A differential peak detector compares the peak signal value at each side of the mixer's differential output, and a differential integrator averages the difference between these peak signal values to provide the measure of bias offset. The corrective network adds a correction offset to each of the local oscillator local oscillator paths on each of the switching pairs that provide the differential output, but opposite to the local oscillator connections.
    Type: Grant
    Filed: July 24, 2002
    Date of Patent: May 19, 2009
    Assignee: NXP B.V.
    Inventor: William Redman-White
  • Publication number: 20090104886
    Abstract: A signal processing device includes: a first converting unit for frequency-converting the input signal into a signal in a first frequency band; a filter for cutting off the frequency component outside a predetermined pass band; a second converting unit for frequency-converting the signal from the first frequency band to a second frequency band; third converting unit for converting the signal in the second frequency band into a signal in a third frequency band coinciding with the pass band; an oscillating unit for oscillating a signal used for frequency conversion of the third converting unit; and a detecting unit for detecting a frequency error between oscillation frequency of the signal oscillated by the oscillating unit and frequency of a signal used for frequency conversion from the second frequency band to the third frequency band coinciding with the pass band, and outputting an error signal indicating the frequency error.
    Type: Application
    Filed: October 20, 2008
    Publication date: April 23, 2009
    Inventors: Takanori MINAMINO, Tamotsu IKEDA
  • Publication number: 20090081985
    Abstract: Aspects of a method and system for a distributed transceiver with DDFS channel selection may include frequency-translating a first signal to generate one or more second signals utilizing a distributed mixer and an in-phase and quadrature mixing stage. The first signal may be an input signal to the distributed mixer, which may comprise a plurality of frequency conversion stages. The input signal to the distributed mixer may be an input signal to at least one of the plurality of frequency conversion stages and an output signal of the distributed mixer may be generated from one or more output signals or the plurality of conversion stages. The output signal from the distributed mixer may be an input signal to the in-phase and quadrature mixing stage and the one or more second signals may be generated from one or more output signals of the in-phase and quadrature mixing stage.
    Type: Application
    Filed: September 24, 2007
    Publication date: March 26, 2009
    Inventors: Ahmadreza Rofougaran, Maryam Rofougaran
  • Patent number: 7509110
    Abstract: A mixer produces an improved output signal during frequency translation of an input signal using a local oscillator (LO) signal. The mixer includes five component mixers connected in parallel. Each component mixer uses a phase-shifted version of the LO signal for frequency translation to produce a component output signal from the input signal. The component output signals are scaled according to corresponding gain factors and combined to form the output signal. When the mixer is used in a receiver, the phases of the component LO signals and the gain factors are configured to substantially cancel overlapping baseband versions of component input signals located at the third, fifth, seventh and ninth harmonics of the LO frequency. When used in a transmitter, the same phase and gain factor configurations substantially cancel third, fifth, seventh and ninth harmonics within the output signal.
    Type: Grant
    Filed: October 31, 2005
    Date of Patent: March 24, 2009
    Assignee: Broadcom Corporation
    Inventors: Takayuki Hayashi, Danilo Manstretta
  • Patent number: 7502605
    Abstract: The invention relates to an imaging device to be used with millimeter and/or sub-millimeter radiation comprising at least a pair of substrates, at least one of which is patterned on at least one surface with a patterning defining at least one radiation detector, each radiation detector comprising: an antenna adapted to receive millimeter and/or sub-millimeter electromagnetic radiation, a mixer channel coupled to said antenna and in communication with a via extending through a substrate for connection to a signal output, a mixer comprising filters being mounted in the mixer channel for extracting an intermediate frequency signal in dependence upon said radiation received by the antenna, a waveguide structure coupled to said mixer and having a signal input for connection to a local oscillator.
    Type: Grant
    Filed: October 27, 2003
    Date of Patent: March 10, 2009
    Assignee: Agence Spatiale Europeenne
    Inventors: Dario Calogero Castiglione, Luisa Deias, Inigo Ederra-Urzainqui, David Brian Haskett, Derek Jenkins, Alexandre Vincent Samuel Bernard Laisne, Alec John McCalden, James Peter O'Neil, Jorge Teniente-Vallinas, Frank Van De Water, Alfred A. Zinn, Peter De Maagt, Chris Mann
  • Patent number: 7496342
    Abstract: Methods, systems, and apparatuses, for down-converting and up-converting an electromagnetic signal. In embodiments the invention operates by receiving an EM signal and recursively operating on approximate half cycles of the carrier signal. The recursive operations can be performed at a sub-harmonic rate of the carrier signal. The invention accumulates the results of the recursive operations and uses the accumulated results to form a down-converted signal. In embodiments, up-conversion is accomplished by controlling a switch with an oscillating signal, the frequency of the oscillating signal being selected as a sub-harmonic of the desired output frequency. When the invention is being used in the frequency modulation or phase modulation implementations, the oscillating signal is modulated by an information signal before it causes the switch to gate the bias signal. The output of the switch is filtered, and the desired harmonic is output.
    Type: Grant
    Filed: October 25, 2004
    Date of Patent: February 24, 2009
    Assignee: Parkervision, Inc.
    Inventors: David F. Sorrells, Michael J. Bultman, Robert W. Cook, Richard C. Looke, Charley D. Moses, Jr., Gregory S. Rawlins, Michael W. Rawlins
  • Patent number: 7493095
    Abstract: A device and a method for processing high data rate serial data includes circuitry for recovering a clock based on the high data rate input data stream. A transceiver includes a coarse loop of a phase-locked loop that selectively provides a clock having accuracy that is within a specified amount. In a sample mode of operation, only the coarse loop PLL is coupled to provide an error signal from which an oscillation signal and clock may be derived. In a second mode (lock) of operation, the transceiver may lock to the received serial data stream by coupling the fine loop PLL to provide an adjusted error signal. In a third mode of operation, (automatic) the transceiver initially performs coarse loop calibration by de-coupling the fine loop PLL and coupling the coarse loop PLL until a steady state has been reached.
    Type: Grant
    Filed: April 25, 2007
    Date of Patent: February 17, 2009
    Assignee: Xilinx, Inc.
    Inventors: Jerry Chuang, William C. Black, Scott A. Irwin
  • Patent number: 7483687
    Abstract: A method and apparatus for frequency down-converting a radio frequency (RF) signal to baseband in two steps using the two quadrature components of a single local oscillator. In the first stage, the RF signal is mixed with both components of the local oscillator signal (LO) in a sub-harmonic mixer to produce an intermediate frequency (IF) output signal having a frequency component at twice the local oscillator frequency minus the RF frequency, i.e., (2×LO)?RF=IF. In the second stage, the IF signal is split into two and supplied to a quadrature mixer that mixes the IF signal with the I component of the same local oscillator signal and separately mixes the IF signal with the Q component of the same local oscillator signal to produce an output signal comprising an I component and a separate Q component at baseband.
    Type: Grant
    Filed: May 11, 2006
    Date of Patent: January 27, 2009
    Inventor: Frederic Carrez
  • Patent number: 7469136
    Abstract: Methods in intermediate frequency and direct conversion receivers for reducing pre-selection filter leakage and harmonic coupling to a programmable voltage controlled oscillator by mixing a receive signal at a mixer having a mixer injection frequency outside a pre-selection filter passband. In some applications, the mixer injection frequency is conditionally moved outside the pre-selection filter passband. In other applications, signal gain is increased to compensate for any loss resulting from shifting the mixer injection frequency outside the pre-selection passband.
    Type: Grant
    Filed: November 30, 2001
    Date of Patent: December 23, 2008
    Assignee: Motorola, Inc.
    Inventors: Matt Hayek, Deven Patel
  • Patent number: 7460849
    Abstract: Techniques to reduce LO leakage by controlling the amplitude of LO signal based on the level of output signal after the frequency conversion process. An LO generator receives a VCO signal and generates an LO signal having a variable amplitude and a frequency that is related to the frequency of the VCO signal. A variable gain amplifier receives a control signal and adjusts the amplitude of the LO signal based on the control signal. The variable amplitude LO signal is used for frequency upconversion (e.g., direction upconversion) of an input signal (e.g., at baseband) to obtain an output signal (e.g., at RF). The relationship between LO signal amplitude and output signal level may be defined by a particular transfer function. In general, the LO signal is set higher for higher output signal level and is reduced proportionally for lower output signal level.
    Type: Grant
    Filed: November 9, 2005
    Date of Patent: December 2, 2008
    Assignee: QUALCOMM Incorporated
    Inventors: Kevin Gard, Anthony Segoria, Gurkanwal (Kamal) Sahota, Charles Persico
  • Patent number: 7460850
    Abstract: A receiving circuit for receiving a high frequency signal is provided which includes a mixer, a local oscillator, a switch circuit, and a controller. The switch circuit switches over between first and second cases. The controller controls in the first case to turn on power supply to the local oscillator, and controls the switch circuit in the first case to output the local oscillation signal outputted from the local oscillator to the mixer, and to output the local oscillation signal through the local oscillation signal output terminal. The controller controls in the second case to turn off power supply to the local oscillator, and controls the switch circuit in the second case to output the local oscillation signal inputted through the local oscillation signal input terminal to the mixer.
    Type: Grant
    Filed: January 20, 2006
    Date of Patent: December 2, 2008
    Assignee: Panasonic Corporation
    Inventor: Mineyuki Iwaida
  • Patent number: 7457599
    Abstract: There is provided a frequency transceiver for automatically controlling a TX/RX IF signal in a radar or a communication system, which transmits/receives an RF signal.
    Type: Grant
    Filed: December 30, 2004
    Date of Patent: November 25, 2008
    Assignee: Korea Aerospace Research Institute
    Inventors: Kyoo Chang Oh, Sang Man Moon, Hyoun Kyoung Kim, In Kyu Kim, Sang Jong Lee, Tae Sik Kim, Hae Chang Lee, Chan Hong Yeom
  • Publication number: 20080254755
    Abstract: In a radio receiver including an aerial wire (1) that receives a radio signal in which a transmission signal is superimposed on a carrier, a (VCXO 2) that oscillates a local oscillation signal, a frequency multiplier (3), and a demodulation circuit that demodulates the transmission signal on the basis of the radio signal and the local oscillation signal, an oscillation frequency control circuit that repeatedly sweeps the frequency of the local oscillation signal over a frequency bandwidth that is equal to or more than the width of a frequency drift in a carrier frequency from the aerial wire (1) or over a frequency bandwidth that is equal to or more than the width of a frequency drift in the local oscillation signal is provided.
    Type: Application
    Filed: September 6, 2005
    Publication date: October 16, 2008
    Inventor: Akira Kato
  • Publication number: 20080242253
    Abstract: According to an embodiment of the invention, there is provided a frequency converter including: an input circuit converting a voltage signal to a current signal; a load circuit supplying a constant current to an input circuit; a first switch circuit configured to output a current signal from the first output terminal in accordance with a switching made in accordance with a first oscillation signal; a second switch circuit configured to output the current signal from the second output terminal in accordance with a switching made in accordance with a second oscillation signal being 180 degrees out of phase with the first oscillation signal; a control circuit generating a control current based on a predetermined reference voltage and an average voltage of the voltages at the first and second output terminals and adding the control current to the current signal of the input circuit.
    Type: Application
    Filed: March 20, 2008
    Publication date: October 2, 2008
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventor: Takafumi Yamaji
  • Patent number: 7421263
    Abstract: A circuit for calibrating a second order intercept point (IP2) and for reducing second order intermodulation (IM2) includes a common mode feedback circuit and a load impedance operatively connected between first and second output terminals of a mixer in a direct conversion receiver. The common mode feedback circuit reduces second order intermodulation of the mixer by detecting an output voltage of the mixer and adjusting a gain of the mixer. The IP2 is controlled by controlling the gain of the common mode feedback circuit. The second order intermodulation (IM2) may be reduced and the linearity of a device may be enhanced.
    Type: Grant
    Filed: December 15, 2004
    Date of Patent: September 2, 2008
    Assignee: Samsung Electronics Co., Ltd.
    Inventor: Woonyun Kim
  • Patent number: 7415262
    Abstract: An access point in a wireless network receives link margin values from associated access points. The access point determines sensitivity values for the associated access points and determines a lower access point output power value from the sensitivity values. Beacons are transmitted at full power and remaining frames are transmitted at the lower access output power. A new access output power may be determined periodically, or when a station associates or disassociates.
    Type: Grant
    Filed: March 29, 2004
    Date of Patent: August 19, 2008
    Assignee: Intel Corporation
    Inventors: Jiewen Liu, Chih C. Tsien
  • Patent number: 7409198
    Abstract: A method (700, 1100) and apparatus (300) are provided in a receiver for applying a variable gain to a received signal including a transmitted codeword in accordance with an Ultra Wideband (UWB) protocol. A first signal is generated and input to a selectable gain stage including a series of selectable 0 dB and 9 dB gain elements (302-305). The first signal includes the received signal mixed with a local oscillator signal modified according to a reference codeword. A gain value is selected from the selectable gain stage to amplify the first signal and form a second signal. An output signal is generated by combining the second signal and the modified local oscillator signal.
    Type: Grant
    Filed: August 30, 2005
    Date of Patent: August 5, 2008
    Assignee: Freescale Semiconductor, Inc.
    Inventors: John W. McCorkle, Phuong T. Huynh
  • Patent number: 7409190
    Abstract: An integrated-circuit element and passive components are mounted on a front face of a multilayer substrate. A capacitor constituting a crystal-oscillator circuit is disposed inside the multilayer substrate. A cavity is provided in a rear face of the multilayer substrate. A crystal oscillator constituting the crystal-oscillator circuit is accommodated in the cavity, and the cavity is sealed with a sealing cap made of a conductive material. The sealing cap is fixed to an electrode pad provided on a motherboard with solder therebetween.
    Type: Grant
    Filed: April 27, 2005
    Date of Patent: August 5, 2008
    Assignee: Taiyo Yuden Co., Ltd
    Inventor: Ryuji Murata
  • Publication number: 20080166985
    Abstract: Systems and methodologies are described that facilitate calibration techniques for a station in a wireless communication system that can be utilized to provide joint estimates for distortion introduced by in-phase and quadrature (I/Q) imbalance and mixing-product modulated images.
    Type: Application
    Filed: January 2, 2008
    Publication date: July 10, 2008
    Applicant: QUALCOMM INCORPORATED
    Inventors: Klaas Wortel, Rainer Gaethke, Vincent K. Jones, James Gardner
  • Patent number: 7398074
    Abstract: An integrated transceiver circuit has a reception path, which in turn has a mixer unit for demodulation of a received signal. An analog/digital converter unit is connected in the reception path downstream from the mixer unit. A first frequency divider is connected between the mixer unit and a voltage controlled oscillator in order to predetermine the demodulation frequency. A second frequency divider is connected between the oscillator and the analog/digital converter unit in order to predetermine the sampling frequency.
    Type: Grant
    Filed: April 12, 2004
    Date of Patent: July 8, 2008
    Assignee: Infineon Technologies
    Inventors: Peter Pfann, Zdravko Boos
  • Publication number: 20080160949
    Abstract: A mixer for down-converting an input signal to an output signal is disclosed. The mixer includes an amplifying circuit and a down-converting circuit. The amplifying circuit is utilized for amplifying the input signal to generate an amplified signal. The down-converting circuit includes a filtering module, a loading module, and a down-converting module. The filtering module is coupled to the amplifying circuit, and is utilized for filtering low-frequency components in the amplified signal. The loading module is coupled to the amplifying circuit and a predetermined voltage level, and is utilized for providing a DC bias voltage to the amplifying circuit. The down-converting module is coupled to the filtering module and the predetermined voltage level, and is utilized for generating the output signal according to a local oscillating signal.
    Type: Application
    Filed: June 26, 2007
    Publication date: July 3, 2008
    Inventors: Jiong-Guang Su, Shyh-Chyi Wong
  • Publication number: 20080157883
    Abstract: According to one exemplary embodiment, a local oscillation generator includes a mixing stage for receiving a primary frequency and one of a number of related frequencies. The local oscillation generator further includes a first transconductance stage to provide a first related frequency to the mixing stage when a first switch selectably enables a first power path in the first transconductance stage. The local oscillation generator further includes a second transconductance stage to provide a second related frequency to the mixing stage when a second switch selectably enables a second power path in the second transconductance stage. The local oscillation generator further includes a number of dividers, where an output of a first divider provides the first related frequency to an input of the first transconductance stage, and where an output of a second divider provides the second related frequency to an input of the second transconductance stage.
    Type: Application
    Filed: December 29, 2006
    Publication date: July 3, 2008
    Inventor: Qiang Li
  • Publication number: 20080136516
    Abstract: A radio frequency (RF) front-end includes a plurality of power amplifier modules and a plurality of impedance matching circuits. Each of the plurality of impedance matching circuits includes an input connection and an output connection, wherein outputs of the plurality of power amplifier modules are coupled to corresponding input connections of the plurality of impedance matching circuits to provide a desired loading of the plurality of power amplifier modules and wherein the output connections of the plurality of impedance matching circuits are coupled together to add power of the plurality of power amplifiers.
    Type: Application
    Filed: April 3, 2007
    Publication date: June 12, 2008
    Applicant: Broadcom Corporation, a California Corporation
    Inventor: Ali Afsahi
  • Patent number: 7386292
    Abstract: Methods, systems, and apparatuses, for down-converting and up-converting an electromagnetic signal. In embodiments the invention operates by receiving an EM signal and recursively operating on approximate half cycles of the carrier signal. The recursive operations can be performed at a sub-harmonic rate of the carrier signal. The invention accumulates the results of the recursive operations and uses the accumulated results to form a down-converted signal. In embodiments, up-conversion is accomplished by controlling a switch with an oscillating signal, the frequency of the oscillating signal being selected as a sub-harmonic of the desired output frequency. When the invention is being used in the frequency modulation or phase modulation implementations, the oscillating signal is modulated by an information signal before it causes the switch to gate the bias signal. The output of the switch is filtered, and the desired harmonic is output.
    Type: Grant
    Filed: October 25, 2004
    Date of Patent: June 10, 2008
    Assignee: ParkerVision, Inc.
    Inventors: David F. Sorrells, Michael J. Bultman, Robert W. Cook, Richard C. Looke, Charley D. Moses, Jr., Gregory S. Rawlins, Michael W. Rawlins
  • Publication number: 20080125072
    Abstract: A signal processing circuit is proposed, which is intended to receive a pair of input signals Sp and Sn in phase opposition on two input terminals and to provide two pairs of output currents SIp and SIn in phase opposition on four output terminals. Each input signal Sp and Sn is amplified in an amplification unit LNAUp and LNAUn and subsequently split in a splitting unit SPLUp and SPLUn. The invention is such that each of the two splitting units SPLUp and SPLUn includes at least two branches, respectively BIp, BQp and BIn, BQn connected between said amplification unit, respectively LNAUp and LNAUn, and one of said output terminals, the four branches BIp, BQp and BIn and BQn each including at least an impedance, respectively RIp, RQp, RIn, RQn, having identical characteristics. Mixer circuits can be easily stacked with this signal processing circuit.
    Type: Application
    Filed: September 15, 2004
    Publication date: May 29, 2008
    Inventor: Herve Jean Francois Marie
  • Patent number: 7379723
    Abstract: In one embodiment, a local oscillator and mixer architecture may include a frequency divider having I and Q channel master storage elements formed of devices of a first size, and I and Q channel slave storage elements formed of devices of a second size, where the second size is smaller than the first size. In such manner, power consumption may be reduced while reducing phase noise in signals provided from the frequency divider to the corresponding mixer.
    Type: Grant
    Filed: July 29, 2004
    Date of Patent: May 27, 2008
    Assignee: Silicon Laboratories Inc.
    Inventor: Aslam Rafi
  • Patent number: 7376410
    Abstract: Methods, systems, and apparatuses for down-converting an electromagnetic (EM) signal by aliasing the EM signal are described herein. Briefly stated, such methods, systems, and apparatuses operate by receiving an EM signal and an aliasing signal having an aliasing rate. The EM signal is aliased according to the aliasing signal to down-convert the EM signal. The term aliasing, as used herein, refers to both down-converting an EM signal by under-sampling the EM signal at an aliasing rate, and down-converting an EM signal by transferring energy from the EM signal at the aliasing rate. In an embodiment, the EM signal is down-converted to an intermediate frequency (IF) signal. In another embodiment, the EM signal is down-converted to a demodulated baseband information signal. In another embodiment, the EM signal is a frequency modulated (FM) signal, which is down-converted to a non-FM signal, such as a phase modulated (PM) signal or an amplitude modulated (AM) signal.
    Type: Grant
    Filed: February 16, 2006
    Date of Patent: May 20, 2008
    Assignee: ParkerVision, Inc.
    Inventors: David F. Sorrells, Michael J. Bultman, Robert W. Cook, Richard C. Looke, Charley D. Moses, Jr.
  • Patent number: 7369835
    Abstract: An image rejection mixer includes a first mixer, a second mixer, a first output adjust circuit, and a second output adjust circuit. The first mixer is coupled to receive an input RF signal and a local oscillator signal and includes a first mixer stage and a first output load stage. The second mixer is coupled to receive the input RF signal and a phase-converted local oscillator signal and includes a second mixer stage and a second output load stage. The first output adjust circuit is coupled to the first output load stage for modifying the signal waveform of a first output signal of the first mixer. The second output adjust circuit is coupled to the second output load stage for modifying the signal waveform of a second output signal of the second mixer. In this manner, the near-perfect image rejection result in the final IF signal can be obtained.
    Type: Grant
    Filed: March 10, 2005
    Date of Patent: May 6, 2008
    Assignee: Xceive Corporation
    Inventors: Didier Margairaz, Pierre Favrat, Alain-Serge Porret, Dominique Python
  • Publication number: 20080102778
    Abstract: Particular embodiments of mixer designs permit greater integration on standard chips with an improvement in power and linearity to enable low-power, high-performance reception. Some embodiments feature a method of frequency conversion using at least two stages of switches to mix an input signal with reference signals. The method involves mixing a differential input signal with a first differential reference signal through a first stage of switches, generating from the first stage of switches a first frequency converted differential signal, and mixing the first frequency converted differential signal with a second differential reference signal through a second stage of switches. The method includes generating from the second stage of switches a second frequency converted differential signal. The first differential reference signal can be phase shifted from the second differential reference signal and can have a different frequency.
    Type: Application
    Filed: June 15, 2007
    Publication date: May 1, 2008
    Inventor: David H. Shen
  • Patent number: 7366485
    Abstract: The circuits of a multimode wireless transmitter are complex and large, and thus difficult to incorporate in a portable wireless device. This problem is solved for a multimode wireless transmitter by enabling the first frequency mode circuit and the second frequency mode circuit to use the same frequency dividers.
    Type: Grant
    Filed: March 2, 2005
    Date of Patent: April 29, 2008
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventor: Atsushi Yoshimoto
  • Patent number: 7366486
    Abstract: An integrated receiver with channel selection and image rejection substantially implemented on a single CMOS integrated circuit is described. A receiver front end provides programable attenuation and a programable gain low noise amplifier. Frequency conversion circuitry advantageously uses LC filters integrated onto the substrate in conjunction with image reject mixers to provide sufficient image frequency rejection. Filter tuning and inductor Q compensation over temperature are performed on chip. The filters utilize multi track spiral inductors. The filters are tuned using local oscillators to tune a substitute filter, and frequency scaling during filter component values to those of the filter being tuned. In conjunction with filtering, frequency planning provides additional image rejection. The advantageous choice of local oscillator signal generation methods on chip is by PLL out of band local oscillation and by direct synthesis for in band local oscillator.
    Type: Grant
    Filed: May 19, 2003
    Date of Patent: April 29, 2008
    Assignee: Broadcom Corporation
    Inventors: Pieter Vorenkamp, Klaas Bult, Frank Carr
  • Patent number: 7363018
    Abstract: Described are a method and a device for high speed transmission of a data signal across an electrical interconnect in an integrated circuit. An optical carrier is modulated with a local oscillator signal at a modulation frequency substantially greater than the data signal to generate an optical local oscillator signal. Phototransducers at the ends of the interconnect illuminated by the optical local oscillator signal generate electrical local oscillator signals. At the transmit end of the interconnect, the data signal is mixed with an electrical local oscillator signal to generate an upconverted data signal. After transmission across the interconnect to the receive end, the upconverted data signal is mixed with the electrical local oscillator signal to retrieve the original data signal.
    Type: Grant
    Filed: January 18, 2005
    Date of Patent: April 22, 2008
    Assignee: Massachusetts Institute of Technology
    Inventors: Brian Tyrrell, Robert Reich
  • Patent number: 7356318
    Abstract: A quadrature subharmonic mixer comprises a polyphase filter configured to generate quadrature components of a local oscillator (LO) reference signal, a summing and scaling element configured to create additional components of the LO reference signal, and a plurality of mixer elements configured to multiply the quadrature components of the LO reference signal and the additional components of the LO reference signal with a radio frequency (RF) signal to obtain a downconverted version of the RF signal.
    Type: Grant
    Filed: July 2, 2004
    Date of Patent: April 8, 2008
    Assignee: Skyworks Solutions, Inc.
    Inventor: Tirdad Sowlati
  • Patent number: 7356324
    Abstract: The invention is directed to a receiver arrangement, for example, in a mobile radio, which allows the use of slowly locking phase locked loops for a point-to-point connection between two transceivers, even in the case of a heterodyne receiver structure. The need to change channels between a transmission slot and a reception slot is avoided by virtue of a changeover device being provided for the purpose of interchanging the in-phase and quadrature components at the input side on a down-conversion frequency mixer. This advantageously allows either the upper sideband or the lower sideband of a useful signal to be down-converted without the need to change channel.
    Type: Grant
    Filed: December 23, 2004
    Date of Patent: April 8, 2008
    Assignee: Infineon Technologies AG
    Inventors: Markus Hammes, Stefan Van Waasen
  • Publication number: 20080081568
    Abstract: A transmitter and receiver circuit includes antennas for receiving high-frequency signals; a local oscillator for generating local oscillation signals; mixers connected to respective antennas for converting the frequency of the high-frequency signals from corresponding antennas in response to the high-frequency signals input from the local oscillator; and a switch for inputting the local oscillation signals generated by the local oscillator into a selected one of the mixers so that receiving channels are switched by the switch.
    Type: Application
    Filed: January 16, 2007
    Publication date: April 3, 2008
    Applicant: MITSUBISHI ELECTRIC CORPORATION
    Inventor: Ko KANAYA
  • Patent number: 7349680
    Abstract: In RF transceivers, a method and system for using phase shift key (PSK) sync word for fine tuning frequency adjustment are provided. One aspect of the invention provides for adjusting a local oscillator frequency in a radio frequency (RF) receiver when a residual DC offset remains after a coarse frequency offset adjustment if performed. The fine adjustment may be necessary because of the synchronization required with a PSK-based modulated portion of a Bluetooth packet. A residual phase shift detected in a sync sequence portion of the Bluetooth packet may be utilized to determine a residual or fine frequency adjustment. This approach may allow an RF receiver to operate, in some instances, without the need for an equalizer. In this regard, the power consumed by the RF receiver may be minimized and/or the overall cost of the RF receiver may be reduced.
    Type: Grant
    Filed: April 8, 2005
    Date of Patent: March 25, 2008
    Assignee: Broadcom Corporation
    Inventors: Brima Ibrahim, Hea Joung Kim, Henrik Tholstrup Jensen, Siukai Mak
  • Patent number: 7324796
    Abstract: A sub harmonic mixer has improved electrical performance in a small package size. The mixer has a low temperature co-fired ceramic substrate. Coupled lines are located within the substrate and connected to an LO port, an RF port and an intermediate frequency port. Three capacitors are formed within the substrate. Vias extend through the substrate. A diode package is mounted on the substrate.
    Type: Grant
    Filed: March 7, 2005
    Date of Patent: January 29, 2008
    Assignee: Scientific Components
    Inventor: Daxiong Ji